A variety of skin plate products are known which consist of or comprise a skin-friendly adhesive material which may e.g. comprise a continuous phase containing the adhesive. In these products there is often a discontinuous phase, which comprises e.g. one or more water-soluble or water-swellable hydrocolloids, starch derivatives or cellulose derivatives or hydrophilic polymers, and optionally one or more medicaments.
WO 89/05619 describes a skin plate product consisting of a matrix material and a plurality of alternating zones of a different material where at least one material is a self adhesive. In this product the zones of the second material extend through the entire thickness of the product and the zones are parallel and extend in a direction usually at right angles to the main surfaces of the product. Such a product may be produced by laminating and rolling plates or sheets of the two materials and then cutting the rolled product perpendicularly to the axis thereof.
WO 94/15562 describes a skin plate product consisting essentially of the same materials as described in WO 89/05619. According to WO 94/15562 the skin plate product comprises at least two material units being of different materials, at least one of which is a skin-friendly self-adhesive material and where a first material unit extends through the area of the entire product forming a matrix, this material unit further constituting at least a portion of the first surface and the second surface, respectively and the additional material unit or units constituting the other portion of the first and the second surface, respectively. Typically, the additional unit comprises a material which is different from the matrix material and extends somewhat into the product but not entirely through the product and the product therefore has different properties on opposite sides. These products are produced when pressing the second material into the matrix material.
Hence, the production methods described in the art are characterized by being very cumbersome and/or limiting the possible choice of materials strongly. If complex distributions of the material units or fine details are needed the production easily becomes unwieldy and exceedingly expensive. Slight changes to the design of a skin plate product usually involves time consuming replacement of major components of the production machinery or even that a different process much be used. This severely increases the cost of introducing new products and the production of small series. The inflexibility of the prior art methods strongly limits the types of skin plate products, which are technically feasible and economically viable.